1. Technical Field
The present invention relates in general to data processing.
2. Description of the Related Art
A number of trends currently influence the development of server-class and mainframe computer systems. In particular, transistor densities within integrated circuits continue to increase according to Moore's Law, which in its current formulation posits that the number of transistors per unit area on integrated circuits will double approximately every 18 months. In addition, processor frequencies continue to double approximately every 2 years. Furthermore, system scale (i.e., the number of central processing units (CPUs) in the system) continues to grow to tens, hundreds, and in some cases, even thousands of processors. The result of these trends is that peak performance of server-class and mainframe computer systems has escalated rapidly, with recently developed large-scale high performance computing (HPC) systems boasting peak performance figures in the hundreds of TFLOPS (trillion floating-point operations per second).
Unfortunately, sustained performance in high performance computing systems has not improved at the pace of peak performance, and in fact, the ratio of sustained performance to peak performance while presently low (e.g., 1:10) is generally declining. With such unutilized computational capacity available, significant attention is now being devoted to achieving greater sustained performance.